We showed up at 6:00 p.m. went up the right side and had to check every site by either walking down the paths or driving. All were full. There could be many more great sites but were for some reason marked as “no camping”. Definitely need a 4x4 for most of the road on the mountain. Be aware that going down on the left side there are no more sites until you get to the bottom. Great views of the Tetons if you can get there early!